Viscount Ashbrook is a title in the Peerage of Ireland. It was created in 1751 for Henry Flower, 2nd Baron Castle Durrow. The title of Baron Castle Durrow, in the County of Kilkenny, had been created in the Peerage of Ireland in 1733 for his father William Flower. He was a Colonel in the Army and also represented County Kilkenny and Portarlington in the Irish House of Commons. He was praised by Jonathan Swift as "a gentleman of very great sense and wit". As of 2022, the titles are held by the eleventh Viscount, who succeeded his father in 1995.